Abstract: The gametophyte development of Davallia formosana Hayata and Humata repens(L.f.) Diels of Davalliaceae was studied for uhe first time in this paper.The spores of two species are all monolete,ellipsoid,and without perispore.The spore germination of both species is Vittaria-type.Their adult prothallia are cordate,with trichomes on the edges and surfaces.The antheridium and archegonium are the same type as that found in leptosporangiate homosporous ferns.The characteristics of gametophyte development of D.formosana and H.repens,such as the spore size,the border cell shape of prothallium,the forms of antheridium and archegonium,and the time of trichome development were summarized.The possibly systematic significance of hardiness,vegetative propagation,and rhizoid function of gametophytes of two species were discussed.